Quality of service based resource determination and allocation apparatus and procedure in high speed packet access evolution and long term evolution systems

ABSTRACT

A wireless transmit receive unit and method disclose processing communication data in a hierarchy of processing layers including a physical (PHY) layer, a medium access control (MAC) layer, and higher layers. A MAC layer transport format selection device (TFSD) assigns higher layer transmission data to parallel data streams based on data characteristics received from higher layers and physical resource information received from the PHY layer. The TFSD generates transport format parameters for each data stream. A multiplexer component multiplexes transmission data onto parallel data streams in transport blocks according to data stream assignment and transport format parameters generated by the TFSD and outputs the selectively multiplexed transmission data to the PHY layer for transmission over physical resource partitions. The TFSD generates physical transmission attributes such as modulation and coding rate, number of subframes per transmission time interval (TTI), duration of TTI, transmission power, and hybrid automatic repeat request (HARQ) parameters.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/669,425 filed Jan. 31, 2007, which issues as U.S. Pat. No. 8,401,036on Mar. 19, 2013, which claims the benefit of U.S. Provisional PatentApplication No. 60/838,318 filed on Aug. 17, 2006 and U.S. ProvisionalPatent Application No. 60/765,078 filed on Feb. 3, 2006, which areincorporated by reference as if fully set forth.

FIELD OF THE INVENTION

The present invention is related to the medium access control (MAC)design of high speed packet access evolution (HSPA+), and long termevolution (LTE) systems. More particularly, the present invention isrelated to a method and apparatus for assigning physical resources andtransport format attributes to a plurality of parallel data streamsaccording to quality of service (QoS) requirements of data to betransmitted in a common transmission time interval (TTI).

BACKGROUND OF THE INVENTION

Wireless communication systems are well known in the art. Communicationsstandards are developed in order to provide global connectivity forwireless systems and to achieve performance goals in terms of, forexample, throughput, latency and coverage. One current standard inwidespread use, called Universal Mobile Telecommunications Systems(UMTS), was developed as part of Third Generation (3G) Radio Systems,and is maintained by the Third Generation Partnership Project (3GPP).

A typical UMTS system architecture in accordance with current 3GPPspecifications is depicted in FIG. 1. The UMTS network architectureincludes a Core Network (CN) interconnected with a UMTS TerrestrialRadio Access Network (UTRAN) via an Iu interface. The UTRAN isconfigured to provide wireless telecommunication services to usersthrough wireless transmit receive units (WTRUs), referred to as userequipments (UEs) in the 3GPP standard, via a Uu radio interface. Acommonly employed air interface defined in the UMTS standard is widebandcode division multiple access (W-CDMA). The UTRAN has one or more radionetwork controllers (RNCs) and base stations, referred to as Node Bs by3GPP, which collectively provide for the geographic coverage forwireless communications with UEs. One or more Node Bs is connected toeach RNC via an Iub interface; RNCs within a UTRAN communicate via anIur interface.

The Uu radio interface of a 3GPP system uses Transport Channels (TrCHs)for transfer of user data and signaling between UEs and Node Bs. In 3GPPcommunications, TrCH data is conveyed by one or more physical channelsdefined by mutually exclusive physical resources, or shared physicalresources in the case of shared channels. TrCH data is transferred insequential groups of Transport Blocks (TBs) defined as Transport BlockSets (TBSs). Each TBS is transmitted in a given Transmission TimeInterval (TTI) which may span a plurality of consecutive system timeframes. For example, according to the 3GPP UMTS Release '99 (R99)specification, a typical system time frame is 10 microseconds and TTIsare specified as spanning 1, 2, 4 or 8 of such time frames. According tohigh speed downlink packet access (HSDPA), an improvement to the UMTSstandard part of Release 5 specifications, and high speed uplink packetaccess (HSUPA), part of Release 6 specifications, TTIs are typically 2ms and therefore are only a fraction of a system time frame.

The processing of TrCHs into a Coded Composite TrCH (CCTrCH) and theninto one or more physical channel data streams is explained, forexample, with respect to time division duplex (TDD) communications in3GPP TS 25.222. Starting with the TBS data, Cyclic Redundancy Check(CDC) bits are attached and Transport Block concatenation and Code Blocksegmentation is performed. Convolution coding or turbo coding is thenperformed, but in some instances no coding is specified. The steps aftercoding include radio frame equalization, a first interleaving, radioframe segmentation and rate matching. The radio frame segmentationdivides the data over the number of frames in the specified TTI. Therate matching function operates by means of bit repetition or puncturingand defines the number of bits for each processed TrCH which arethereafter multiplexed to form a CCTrCH data stream.

In a conventional 3GPP system, communications between a UE and a node Bare conducted using a single CCTrCH data stream, although the node B maybe concurrently communicating with other UEs using respective otherCCTrCH data streams.

The processing of the CCTrCH data stream includes bit scrambling,physical channel segmentation, a second interleaving and mapping ontoone or more physical channels. The number of physical channelscorresponds to the physical channel segmentation. For uplinktransmissions, UE to Node B, the maximum number of physical channels fortransmission of a CCTrCH is currently specified as two. For downlinktransmissions, Node B to UEs, the maximum number of physical channelsfor transmission of a CCTrCH is currently specified as sixteen. Eachphysical channel data stream is then spread with a channelization codeand modulated for over air transmission on an assigned frequency.

In the reception/decoding of the TrCH data, the processing isessentially reversed by the receiving station. Accordingly, UE and NodeB physical reception of TrCHs require knowledge of TrCH processingparameters to reconstruct the TBS data. For each TrCH, a TransportFormat Set (TFS) is specified containing a predetermined number ofTransport Formats (TFs). Each TF specifies a variety of dynamicparameters, including TB and TBS sizes, and a variety of semi staticparameters, including TTI, coding type, coding rate, rate matchingparameter and CRC length. The predefined collection of TFSs for theTrCHs of a CCTrCH for a particular frame is denoted as a TransportFormat Combination (TFC). For each UE a single TFC is selected per TTIso that there is one TFC processed per TTI per UE.

Receiving station processing is facilitated by the transmission of aTransport Format Combination Indicator (TFCI) for a CCTrCH. For eachTrCH of a particular CCTrCH, the transmitting station determines aparticular TF of the TrCH's TFS which will be in effect for the TTI andidentifies that TF by a Transport Format Indicator (TFI). The TFIs ofall the TrCHs of the CCTrCH are combined into the TFCI. For example, iftwo TrCHs, TrCH1 and TrCH2, are multiplexed to form CCTrCH1, and TrCH1has two possible TFs, TF10 and TF11, in its TFS and TrCH2 has fourpossible TFs, TF20, TF21, TF22, and TF23, in its TFS, valid TFCIs forCCTrCH1 could include (0,0), (0,1), (1,2) and (1,3), but not necessarilyall possible combinations. Reception of (0,0) as the TFCI for CCTrCH1informs the receiving station that TrCH1 was formatted with TF10 andTrCH2 was formatted with TF20 for the received TTI of CCTrCH1; receptionof (1,2) as the TFCI for CCTrCH1 informs the receiving station thatTrCH1 was formatted with TF11 and TrCII2 was formatted with TF22 for thereceived TTI of CCTrCII1.

In UMTS specification releases 5 and 6 pertaining to HSDPA and HSUPA,respectively, fast retransmissions are accomplished according to hybridautomatic repeat request (HARQ). There it is currently specified thatonly one hybrid automatic repeat request (HARQ) process is used per TTI.

High speed packet access evolution (HSPA+) and universal terrestrialradio access (UTRA) and UTRAN long term evolution (LTE) are part of acurrent effort lead by 3GPP towards achieving high data-rate,low-latency, packet-optimized system capacity and coverage in UMTSsystems. In this regard, both HSPA+ and LTE are being designed withsignificant changes to existing 3GPP radio interface and radio networkarchitecture. For example, in LTE, it has been proposed to replace codedivision multiple access (CDMA) channel access, used currently in UMTS,by orthogonal frequency division multiple access (OFDMA) and frequencydivision multiple access (FDMA) as air interface technologies fordownlink and uplink transmissions, respectively. The air interfacetechnology proposed by HSPA+ is based on code division multiple access(CDMA) but with a more efficient physical (PHY) layer architecture whichcan include independent channelization codes distinguished with respectto channel quality. Both the LTE and HSPA+ are being designed formultiple-input multiple-output (MIMO) communications physical layersupport. In such new systems, multiple data streams can be used forcommunications between a UE and a Node B.

The inventors have recognized that the existing 3GPP medium accesscontrol (MAC) layer procedures are not designed to deal with the new PHYlayer architectures and features of the proposed systems. TFC selectionin the current UMTS standard does not take into account some of the newtransport format (TF) attributes introduced by LTE and HSPA+ including,but not limited to, time and frequency distribution and number ofsubcarriers in LTE, channelization codes in HSPA+, and different antennabeams in the case of MIMO.

According to the MAC procedures defined in the current UMTS standard,data multiplexed into transport blocks is mapped to a single data streamat a time, such that only one transport format combination (TFC)selection process is required to determine the necessary attributes fortransmission over the physical channel starting at a common transmissiontime interval (TTI) boundary. Accordingly, only one hybrid automaticrepeat request (HARQ) process, which controls data retransmissions forerror correction, is allocated for any given UE-Node B communication.According to the proposed PHY layer changes for HSPA+ and UMTS describedabove, for a given UE-Node B communication, multiple physical resourcegroups may be available simultaneously for data transmissions, resultingin potentially multiple data streams to be transmitted for thecommunication.

The inventors have recognized that, starting at a common TTI boundary,multiple data streams may each have common or different quality ofservice (QoS) requirements, requiring specialized transmissionattributes, such as modulation and coding, and different hybridautomatic repeat request (HARQ) processes. By way of example, in thecase of multiple-input multiple-output (MIMO) communications,independent data streams can be transmitted simultaneously because ofspatial diversity; however, each spatially diverse data stream requiresits own transmission attributes and HARQ process to meet its desired QoSrequirements because of different channel characteristics. There arecurrently no MAC methods or procedures to assign attributes to multipledata streams simultaneously and to effectively provide equal or unequalQoS to parallel data streams.

The inventors have developed a method for selecting multiple transportformats in parallel according to channel quality measurements and QoSrequirements that exploits the new PHY layer attributes and features ofHSPA+ and LTE systems.

SUMMARY

The present invention provides a method and apparatus for transportformat combination (TFC) selection in a medium access control (MAC)layer to deal with changes proposed by high speed packet accessevolution (HSPA+) and long term evolution (LTE) systems includingphysical layer structure and attributes, dynamic resource allocation,transmission schemes becoming MIMO, and multiple QoS requirements. Amethod is provided for running multiple TFC selection proceduressimultaneously to assign transmission attributes to parallel datastreams satisfying the quality of service (QoS) requirements of the dataaccording to the physical channel characteristics. The present inventionsupports the transmission of a plurality of data streams on a commontransmission time interval (TTI) boundary with either normalized ordifferentiated QoS via the parallel TFC selection functions. Substantialchanges are introduced to the previous 3GPP TFC selection procedure,defined in the high speed downlink packet access (HSDPA) and high speeduplink packet access (HSUPA) protocols which address new features inHSPA+ and LTE systems as described above. The present invention readilyprovides for dynamic hybrid automatic repeat request (HARQ) processassignment when different HARQs are applicable to the data streams.

For a preferred embodiment, a wireless transmit receive unit (WTRU),that includes a receiver and a transmitter, and method are provided thatprocess communication data in a hierarchy of processing layers includinga physical (PHY) layer, a medium access control (MAC) layer and higherlayers. A MAC layer transport format selection device defines anassignment of higher layer transmission data to parallel data streamsbased on data characteristics received from higher layers and physicalresource information received from the PHY layer. The transport formatselection device also generates transport format parameters for eachdata stream. A multiplexer component multiplexes the transmission dataonto the parallel data streams in transport blocks in accordance withthe data stream assignment and the respective transport formatparameters generated by the transport format selection device andoutputs the selectively multiplexed transmission data to the PHY layerfor transmission over respective physical resource partitions via one ormore antennas for transmitting wireless signals. Preferably, thetransport format selection device also generates physical transmissionattributes such as modulation and coding rate (MCR), number of subframesper transmission time interval (TTI), duration of TTI, transmissionpower and hybrid automatic repeat request (HARQ) parameters.

Other objects and advantages will be apparent to those of ordinary skillin the art based upon the following description of presently preferredembodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

A more detailed understanding of the invention may be had from thefollowing description, given by way of example and to be understood inconjunction with the accompanying drawings wherein:

FIG. 1 shows an overview of the system architecture of a conventionalUMTS network.

FIG. 2 shows the application of parallel transport format combination(TFC) selection functions each TTI within the medium access (MAC) layerto support the physical layer features of proposed LTE or HSPA+ systemsin accordance with the present invention.

FIG. 3 is a flow diagram for MAC procedure each TTI applying a pluralityof TFC selection functions to assign data to available physicalresources based on channel quality measurements and quality of servicerequirements in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is applicable to wireless communication systemsincluding, but not limited to, Third Generation Partnership Project(3GPP) long term evolution (LTE) and high speed packet access evolution(HSPA+) systems. The present invention may be used in both uplink (UL)and downlink (DL) communications, and therefore may be used in awireless transmit receive unit (WTRU), also referred to as a userequipment (UE), or a Node B, also referred to as a base station.

In general, a wireless transmit/receive unit (WTRU) includes but is notlimited to a user equipment, mobile station, fixed or mobile subscriberunit, pager, cellular telephone, personal digital assistant (PDA),computer, or any other type of device capable of operating in a wirelessenvironment. A base station is a type of WTRU generally designed toprovide network services to multiple WTRUs and includes, but is notlimited to, a Node-B, site controller, access point or any other type ofinterfacing device in a wireless environment.

A revised MAC protocol is provided to take into account new attributesand resources introduced by high speed packet access evolution (HSPA+)and long term evolution (LTE) systems including, but not limited to,channelization codes for HSPA+, the number and distribution ofsubcarriers in the frequency and time domains for LTE, different antennabeams in multi-input multi-output (MIMO) schemes for HSPA+ and LTE, andsubsets of antennas in MIMO schemes for HSPA+ and LTE. For HSPA+ and LTEsystems employing MIMO, the present invention provides different linkadaptation parameters, for example, different modulation and codingschemes, for each of a plurality of parallel data streams. The pluralityof parallel data streams are assigned to different physical resourcegroups of different spatial channels preferably based on the quality ofservice (QoS) requirements of the data to be transmitted and the channelquality of the channels. Specifically, a method is provided to normalizeQoS across parallel data streams when the same QoS is desired, and torealize different QoS requirements for parallel data streams, when, forexample, the data streams originate from different radio bearers withdifferent QoS requirements.

FIG. 2 illustrates a preferred embodiment of selected componentscomprised in a transmitter and/or receiver associated with multipletransport format combination (TFC) selections each TTI in a mediumaccess (MAC) layer processing component 200 for a WTRU configured tooperate in LTE or HSPA+ systems in accordance with the presentinvention. TFC selection is a process that occurs for each active datastream prior to each transmission time interval (TTI) and is involvedwith deciding how data is to be transmitted.

The medium access (MAC) layer processing component 200 is configured toreceive data from one or more radio bearers 204 ₁ to 204 _(M) via aradio link control protocol (RLC) layer for a given UE-Node Bcommunication link provided by higher layers. The higher layers,including but not limited to the RLC layer, the radio resource control(RRC) layer and layer 3, are represented by higher layer components 203that exist above the MAC layer component 200. The data of the radiobearers 204 ₁ to 204 _(M) is preferably buffered in a buffer 219 in alayer above the MAC layer, for example above the RLC layer, until afterTFC selections for the current TTI have occurred, at which point thedata is multiplexed by data multiplexer component 220 into designatedtransport blocks, as discussed below.

The MAC layer processing component 200 is also configured to receivequality of service (QoS) requirements and other data characteristics 202₁ to 202 _(M) for each radio bearer. QoS requirements provided by higherlayers (i.e. layer 3 or higher) may include, but are not limited to, anumber of hybrid automatic repeat request (H-ARQ) retransmissions, ablock error rate, a priority, allowed data combinations and/or a poweroffset. Other data characteristics can include items such as buffercharacteristics for each channel of data of the radio bearers.

From the physical (PHY) layer, represented by the physical layercomponent 201, the MAC layer processing component 200 receives channelcharacteristics 206 ₁ to 206 _(N) for each group of available physicalresources such as channel quality measurements and dynamic schedulingparameters that are susceptible to change each TTI. A transport formatcombination (TFC) selection device 208 is provided as part of the MAClayer processing component 200. The TFC selection device 208 isconfigured to assign the radio bearer data 204 ₁ to 204 _(M) and theavailable physical resource partitions based on the information 202 ₁ to202 _(M), and 207 communicated from higher layers and the information206 ₁ to 206 _(N) communicated from the PHY layer.

Channel characteristics of available physical resources signaled to theMAC layer each TTI from the PHY layer for the purpose of TFC selectionmay, for example, take the form of a channel quality indicator (CQI) forthe channel quality. Subchannels can be provided as subcarriers in LTE,and channelization codes in HSPA+. The present invention takes intoaccount new dynamic transport format (TF) parameters introduced by LTEand HSPA+ that are susceptible to change for each TTI, including, butnot limited to, permitted transport block (TB) or TB set sizes, numberof subframes, modulation rate, coding rate, time and frequencydistribution of subcarriers (for LTE), number of subchannels (i.e.subcarriers or channelization codes), maximum allowed transmissionpower, antenna beams in MIMO, subset of antennas in MIMO, TTI durationand H-ARQ parameters. These dynamic TF parameters are preferablydetermined in the TFC selection device 208 prior to each TTI based oncorresponding limitations provided by the PHY layer data 206 ₁ to 206_(N).

Some TF parameters are considered semi-static because they take morethan one TTI to change and are accordingly not dynamically updated eachTTI but after multiple TTIs. Examples of semi-static TF parametersinclude the type of channel coding, and the size of the cyclicredundancy check (CRC). Preferably, semi-static parameters aredetermined according to signaling information 207 to the transportformat combination (TFC) selection device 208 from a higher layer suchas, for example, the Radio Resource Control (RRC) layer.

The TFC selection device 208 is configured to assign the radio bearerdata 204 ₁ to 204 _(M) and the available physical resource partitionsinto corresponding parallel TFC selection functions 210 ₁ to 210 _(N)that assign the radio bearer data 204 ₁ to 204 _(M) to respective datastreams 209 ₁ to 209 _(N) and identify respective HARQ processes 230 ₁to 230 _(N) to the PHY layer which in turn applies the respective HARQprocesses 240 ₁ to 240 _(N) to the respective data streams. The datastreams 209 ₁ to 209 _(N) may consist of data from one or more logicalchannels, and may each be derived from a single radio bearer or aplurality of radio bearers. Data of a single radio bearer may be dividedand assigned to different data streams determined by the TFC selectiondevice 208. For example, when only one radio bearer is communicatingdata, that radio bearer's data is preferably divided into streams toefficiently use all of the available physical resource partitions,particularly for UL transmissions.

Typically, the available physical resource partitions will be defined inthe information received from the PHY layer 206 ₁ to 206 _(N). Foruplink (UL) transmissions, the TFC selection device may receive explicitpartition instructions from RRC layer signaling 207 dictating physicalresource partitions and transmission parameters for each physicalresource in each partition. Similarly, the signaling from the RRC layer207 may instruct on partitions that are data flow or radio bearerspecific. To the extent permitted, the PHY layer information 206 ₁ to206 _(N) can include optional choices in the groupings of physicalresources for physical partitions. In such case, the TFC selectiondevice 208 will also select the partitions from allowable partitioningcriteria signaled from the PHY layer 206 ₁ to 206 _(N) and/or the RRClayer 207.

The TFC selection device 208 preferably matches data QoS requirements ofthe channel data of the radio bearers 204 ₁ to 204 _(M) to physicalchannel qualities for available physical resource partitions in definingthe data streams 209 ₁ to 209 _(N). The TFC selection device 208provides the assignment of the radio bearers 204 ₁ to 204 _(M) for thedata streams 209 ₁ to 209 _(N) to the data multiplexer component 220 viaassignment data 214 so that the channel data of the radio bearers 204 ₁to 204 _(N) is appropriately directed into the respective assigned datastreams 209 ₁ to 209 _(N). The data streams 209 ₁ to 209 _(N) are eachsomewhat analogous to the prior art single CCTrCH or single TrCH datastream, but represent a selected division of the data of the radiobearers for a communication between a UE and Node B which followindependent processing/transmission tracks.

The TFC selection functions 210 ₁ to 210 _(N) generate transport formats(TFs) or TF sets to provide the desired QoS for the parallel datastreams 209 ₁ to 209 _(N) based on the channel quality parameters of thecorresponding physical resource partitions. The TF selection for eachselected physical resource partition is provided to the PHY layer asrepresented by signals 230 ₁ to 230 _(N). The TFC selection functions210 ₁ to 210 _(N) also preferably make available parameter choices forthe physical resources of physical resource partitions such as number ofsubframes, modulation rate, coding rate, time and frequency distributionof subcarriers (for LTE), number of subchannels (i.e. subcarriers orchannelization codes), maximum allowed transmission power, antenna beamsin MIMO, subset of antennas in MIMO, TTI duration and H-ARQ parameters.These choices will in most instances be limited by the PHY layer.However, the total amount of HARQ resources available may be signaled tothe MAC component 200 to permit the TFC selection functions 210 ₁ to 210_(N) to assign HARQ processes for the data streams 209 ₁ to 209 _(N) viasignals 230 ₁ to 230 _(N) to the PHY layer. The HARQ partitionassignment is affected by the values of other related parameters, inparticular, the values of the modulation and coding scheme (MCS) and TBsize. The TFC selection functions 210 ₁ to 210 _(N) take into accountthe values of physical layer parameters, preferably MCS and TB size, ofeach of the physical resource partitions when determining the HARQpartition assignments for the respective data streams 209 ₁ to 209 _(N).In the more limited case where the PHY layer dictates the HARQ resourcepartitioning, the MAC component 200 does not select the HARQ processesassigned to the data streams 209 ₁ to 209 _(N).

The TF selection including the TB size for each data stream 209 ₁ to 209_(N) is provided via 215 ₁ to 215 _(N) to the data multiplexer component220. The data multiplexer component 220 uses this information toconcatenate and segment respective higher layer data streams 209 ₁ to209 _(N) into transport blocks (TBs) or TB sets 250 ₁ to 250 _(N)designated for the respectively assigned physical resource partitions asdetermined by the TFC selection device 208. The TBs 250 ₁ to 250 _(N)are preferably provided to the PHY layer for transmission over physicalchannels starting on a common transmission time interval (TTI) boundary.Preferably, the PHY layer includes one or more antennas for transmittingthe TBs via wireless signals.

Preferably, signals 230 ₁ to 230 _(N) and TBs 250 ₁ to 250 _(N) arecoordinated in the MAC layer processing component 200 and may becombined and signaled together to the PHY layer processor in advance ofeach TTI boundary.

In one embodiment, the TFC selection functions 210 ₁ to 210 _(N)generate transport formats (TFs) to normalize the expected QoS providedfor two or more of the data stream 209 ₁ to 209 _(N). This embodiment isdesirable when data originates from a radio bearer or set of radiobearers with common QoS requirements to be transmitted in a common TTI.

In another embodiment, the TFC selection functions 210 ₁ to 210 _(N)generate transport formats (TFs) to differentiate the expected QoSprovided to two or more of the data stream 209 ₁ to 209 _(N). Thisalternate embodiment is desirable when two or more radio bearer setsproviding data for the respective data streams have different QoSrequirements, or, when a single radio bearer, for example a voicestream, contains data with different QoS including priority.

As shown in FIG. 3, an example of the basic processing steps 300undertaken in advance of each TTI boundary with respect to the MAC layerin accordance with the invention includes: buffer analysis 305, physicalresource partitioning and data flow assignment 310, transmissionattributes determination 315 and data multiplexing 320. As noted above,the present invention readily provides for HARQ process assignment bythe MAC component when different HARQs are applicable to the datastreams 209 ₁ to 209 _(N).

In step 305, data, corresponding quality of service (QoS) requirementsand possibly other characteristics including physical resource partitionrequirements for the data, are received from higher layers, for examplethe radio resource control (RRC) layer and the radio link control (RLC)layer. Parameters, such as channel quality indicators (CQIs) and dynamicscheduling information, are received from the physical (PHY) layer,preferably prior to a transmission time interval (TTI) in which data isto be transmitted. The high level data information is analyzed incomparison with the PHY layer partition information to determine QoSrequirements of available higher layer data and available physicalresource partitions with associated CQI levels and dynamic schedulinginformation. In step 310, there is an assignment of available physicalresource partitions and parallel data streams derived from the higherlayer channel data by, for example, matching QoS requirements to CQIsand dynamic scheduling information. In step 315, transport formats (TFs)or TF sets associated with each data stream and the assigned physicalresource partition are generated to provide the desired QoS for theparallel data streams based on the channel quality parameters anddynamic scheduling information of the corresponding physical resourcepartitions. In association with this step, parameters for the physicalresources as permitted by the PHY layer are determined. For example, anassignment of HARQ resources is preferably made. In step 320, the higherlayer data is multiplexed (e.g. concatenated and segmented) inaccordance with the data stream assignment into transport blocks (TBs)or TB sets according to the associated TFs for each data streamactivating on the current TTI boundary and provided to the PHY layer fortransmission over physical channels that preferably start on a commontransmission time interval (TTI) boundary. Further explanation of eachstep in general is provided below.

Buffer Analysis

QoS requirements 202 ₁ to 202 _(M), such as data rate, block error rate,transmit power offset, priority and/or latency requirements, for radiobearer data 204 ₁ to 204 _(M) are evaluated by the TFC selection device208. In general, QoS requirements are provided by the higher layers sothat the TFC selection functions may determine the permitted datacombinations for the data multiplexing step for the current TTI(s). Whenmultiple logical channels or higher layer data flows are present in thedata 204 ₁ to 204 _(M), the QoS requirements may further include bufferoccupancy information for each logical channel, priority for eachlogical channel or data flow or indication of the highest priority dataflow, packet sizes for each data flow, and allowed combinations of dataflows. According to the QoS requirements 202 ₁ to 202 _(M), the TFCselection device 208 preferably determines the allowed data multiplexingcombinations for data channels 204 ₁ to 204 _(M), with available datafor transmission, sorted by transmission priority. The amount ofavailable data for each allowed multiplexing combination, acorresponding number of HARQ retransmissions, a power offset and/orother QoS related parameters associated with each data multiplexingcombination are also preferably determined.

Physical Resource Partitioning and Data Flow Assignment

The available physical resources, as provided by the physical layeralong with channel quality measurements and dynamic schedulinginformation 206 ₁ to 206 _(N), are preferably partitioned intosubchannel partitions based on the QoS and partitioning requirements ofhigher layer data and channel parameters provided by the physical (PHY)layer including, but not limited to, channel quality indicator (CQI)reports, dynamic scheduling information, and available HARQ resources.The available subchannel partitions are determined so that they may beassigned data streams for the individual transmission of multiplexeddata combinations belonging to those data streams.

According to a preferred embodiment, a CQI report is generated for eachavailable subchannel (subcarriers in the time and frequency domains orchannelization-code in the code domain) measured based on pilot channelsat the physical layer. In downlink (DL) communications, not all theavailable subchannels are necessarily used for data transmission eachTTI. A threshold indicating the desired limit of acceptable transmissionperformance is defined such that only those subchannels withcorresponding CQI values higher than the threshold are used fortransmission. Accordingly, only the qualifying subchannels are selectedby the TFC selection functions 210 ₁ to 210 _(N) for inclusion inassigned partitions. This is preferably accomplished by CQI basedscheduling in a Node B.

For UL communications, a Node B scheduler may provide to a userequipment (UE) information on the allocated physical (PHY) resources,including, but not limited to, the available subchannels, antenna beams,maximum allowed uplink (UL) power, and the modulation and coding scheme(MCS) limitation and/or channel quality indicator (CQI) for each of theallocated subchannels. Preferably, such information is provided for eachphysical channel available for the UL transmission. The PHY resourceallocation may change or remain unchanged for the subsequent schedulinggrants. This may be determined by identifying the relative difference insubsequent scheduling grants. A UE may not be provided with enoughphysical resources to selectively choose a subset set of the availablesubchannels based on a threshold value. In this case, the TFC selectiondevice 208 may preferably make use of all available subchannelsregardless of CQI. UL channels offering CQI greater than a threshold maybe identified in the scheduling grant. However, if the grant is validover multiple TTIs, the CQI of individually granted subchannels may varyover time. The TFC selection functions 210 ₁ to 210 _(N) preferablyadjust the modulation and coding set (MCS), TB size, transmission powerand/or HARQ retransmissions for each subchannel or sets of subchannelsassigned to a particular physical resource partition, according to thetransmission attributes determination step explained below. The TFCselection functions 210 ₁ to 210 _(N) preferably segregate data flowsbetween subchannels or sets of subchannels assigned to a particularphysical resource partition offering CQI levels that better accommodatethe QoS requirement of the data flows 209 ₁ to 209 _(N) mapped to thephysical resource partition.

Parallel data streams derived from the higher layer data 204 ₁ to 204_(M) are assigned to the TFC selection functions 210 ₁ to 210 _(N) inconnection with respective available physical resource partitions. Thedata stream assignments are preferably generated according to common QoSattributes of various channels among the higher layer data 204 ₁ to 204_(M), for example, priority. TFC selection functions 210 ₁ to 210 _(N)preferably assign data streams to available physical resource partitionsby matching CQI levels and dynamic scheduling information to QoSrequirements as best as possible for each set of data flows andassociated physical resource partitions.

The parallel data streams may derive from one or more radio bearers withcommon or different QoS requirements; accordingly, two or more of thedata streams 209 ₁ to 209 _(N) may have compatible QoS requirements. Byway of example, voice over internet protocol (VoIP) and internetbrowsing data requiring non-compatible QoS can be assigned to differentdata streams 209 ₁ to 209 _(N) or sets of data streams and mapped toseparate physical resource partitions to best match the differentpriority and delay requirements.

Transmission Attributes Determination

The TFC selection functions 210 ₁ to 210 _(N) preferably operate inparallel to determine the TF and physical transmission attributes to beapplied to each physical resource partition to best satisfy the QoSrequirements of the corresponding data streams 209 ₁ to 209 _(N). Thisdetermination is preferably based on the CQIs and dynamic schedulinginformation of each subchannel partition and the QoS requirements of thecorresponding data streams 209 ₁ to 209 _(N). The physical attributesinclude the modulation and coding rate, number of subframes per TTI,transmission power and HARQ retransmissions which may be adjusted tomeet the QoS requirement of each data flow and possibly according to theCQI of particular subchannels. HARQ processes are preferably assigned tophysical resource partitions dynamically, as explained in more detailbelow.

More than one physical resource partition may be associated with datastreams with common QoS requirements. In this case, if the CQIs varyacross individual physical resource partitions, the transport formatparameters, including modulation and coding set (MCS), TB size, TTIlength, transmission power and HARQ parameters, are adjusted tonormalize QoS across the subchannel partitions. In other words,different parameters may be assigned for each physical resourcepartition to normalize the QoS over the corresponding data streams whichmay be any subset of the data streams 209 ₁ to 209 _(N). Some TFattributes may be adjusted relative to each other if they affect thesame QoS attributes, for example in the case of MCS and transmissionpower both affecting the expected block error rate.

Once the coding, modulation and TTI length have been associated with thephysical resource partitions, transport blocks TBs (or, equivalently, TBsets) are assigned. In particular, the number of data bits that can bemultiplexed into each TB for each subchannel partition is preferablydetermined based on the other TF parameters. There may be several TBswith uniquely defined sizes associated with different physical resourcepartitions and HARQ processes. In the case dynamic HARQ resourcepartitioning is allowed, the sum of the subchannel set transmissioncapabilities may not exceed the total available HARQ resources. Whendynamic HARQ resource partitioning is not allowed, the selected TF maynot exceed the available resources for each associated HARQ process.

The TBs 250 ₁ to 250 _(N) are provided to the physical layer, along withassociated TF attributes 230 ₁ to 230 _(N), for transmission overphysical channels.

HARQ Assignment

In accordance with a preferred embodiment, HARQ resources aredynamically distributed over the physical resource partitions and theirassociated TBs (or, equivalently, TB sets) such that multiple HARQprocesses may be assigned prior to each TTI. This is preferred overstatically configured HARQ process resources proposed by the prior artbecause when static HARQ process resources are applied, physicalresource partitions are restricted to match the HARQ resourcesassociated with the physical resource partition.

Dynamic distribution of HARQ resources allows far greater flexibilityduring physical resource partitioning since the total HARQ resources canbe divided dynamically on an as-needed basis among the data multiplexedonto each physical resource partition. Therefore, the partitioning ofphysical resources is not restricted by static resources of theassociated HARQ process. Additionally, when data of one higher layerradio bearer is distributed across several physical resource partitionsoffering different channel quality, there is far greater flexibility inchoosing the size of each TB and the MCS associated with the physicalresource partitions to accommodate the desired QoS.

Each TB associated with one or more subchannel sets is assigned to anavailable HARQ process. If dynamic HARQ resource partitioning isallowed, the TB size and MCS assigned to the TB are preferably used todetermine a soft memory requirement, which is then used to identify tothe transmitter and receiver the required HARQ resources. For example, atransport format combination indicator (TFCI) or transport format andresource indicator (TFRI) and knowledge of the chosen MCS at thereceiver are typically sufficient for a receiver to dynamically reserveHARQ memory resources on a TTI basis. In synchronous operation theretransmissions are known. In asynchronous operation, HARQ processidentities are used to indicate retransmissions. Preferably whenretransmissions occur, the HARQ resources are not dynamically adjustedfor the retransmissions because the resource requirements do not changefrom the initial transmission.

A HARQ process 240 ₁ to 240 _(N) is assigned to each TB and itsassociated physical resource partition. Information 230 ₁ to 230 _(N)including, but not limited to, the MCS, subframes, TTI, subcarriers orchannelization-codes, antenna (in MIMO), antenna power, and maximumnumber of transmissions, are then given to HARQ process fortransmission. The HARQ processes 240 ₁ to 240 _(N) will then indicateits availability upon reception of a successful deliveryacknowledgement, or upon exceeding its maximum number ofretransmissions.

Data Multiplexing

The data multiplexer component 220 multiplexes the higher layer data 204according to data flow assignment information 214 and TF attributes 215₁ to 215 _(N) as provided by the TFC selection functions 210 ₁ to 210_(N). Data blocks for each data flow are multiplexed into the previouslydetermined TB sizes associated. Knowledge of the physical resourcepartitions to which the data flows 209 ₁ to 209 _(N) will be directed isnot required for multiplexing; only the TB sizes and mapping of logicalchannels 204 ₁ to 204 _(M) to data flows 209 ₁ to 209 _(N) are needed.Preferably, multiplexing of logical channels 204 ₁ to 204 _(M) into TB'sassigned to data streams 209 ₁ to 209 _(N) is done in order of priorityof the logical channels 204 ₁ to 204 _(M).

If there is less available data than the TB size or the multiplexingblock size does not exactly fit, the TB may be padded accordingly.However, the TFC selection processes 210 ₁ and 210 _(N) preferablyeliminates the need for padding in most instances. If the available datafor transmission exceeds the TB size and more than one TB has beendetermined for the set of associated data flows, the blocks from theassociated data flows are distributed across the TBs. Within each TB,MAC header information specifies how data flows have been multiplexedwithin the TB. This information uniquely identifies how data fromdifferent flows have been multiplexed within a common TB, and how datafrom flows have been distributed across TBs.

The features of the present invention may be incorporated into anintegrated circuit (IC) or be configured in a circuit comprising amultitude of interconnecting components.

Although the features and elements of the present invention aredescribed in the preferred embodiments in particular combinations, eachfeature or element can be used alone without the other features andelements of the preferred embodiments or in various combinations with orwithout other features and elements of the present invention. Themethods or flow charts provided in the present invention may beimplemented in a computer program, software, or firmware tangiblyembodied in a computer-readable storage medium for execution by ageneral purpose computer or a processor. Examples of computer-readablestorage mediums include a read only memory (ROM), a random access memory(RAM), a register, cache memory, semiconductor memory devices, magneticmedia such as internal hard disks and removable disks, magneto-opticalmedia, and optical media such as CD-ROM disks, and digital versatiledisks (DVDs).

Suitable processors include, by way of example, a general purposeprocessor, a special purpose processor, a conventional processor, adigital signal processor (DSP), a plurality of microprocessors, one ormore microprocessors in association with a DSP core, a controller, amicrocontroller, Application Specific Integrated Circuits (ASICs), FieldProgrammable Gate Arrays (FPGAs) circuits, any integrated circuit,and/or a state machine.

A processor in association with software may be used to implement aradio frequency transceiver for in use in a wireless transmit receiveunit (WTRU), user equipment, terminal, base station, radio networkcontroller, or any host computer. The WTRU may be used in conjunctionwith modules, implemented in hardware and/or software, such as a camera,a video camera module, a videophone, a speakerphone, a vibration device,a speaker, a microphone, a television transceiver, a hands free headset,a keyboard, a Bluetooth® module, a frequency modulated (FM) radio unit,a liquid crystal display (LCD) display unit, an organic light-emittingdiode (OLED) display unit, a digital music player, a media player, avideo game player module, an Internet browser, and/or any wireless localarea network (WLAN) module.

What is claimed is:
 1. A network node comprising: means for receiving achannel quality indicator (CQI) report from a wireless transmit/receiveunit (WTRU) indicating for each of a plurality of transport blocks arespective CQI; and means in response to the received CQI report fortransmitting a plurality of transport blocks to the WTRU in a commontransmission time interval.
 2. The network node of claim 1 wherein adifferent Hybrid Automatic Repeat Request (HARQ) process is used foreach transport block; wherein the HARQ processes are asynchronous andthe network node identifies the HARQ processes for each transport block.3. The network node of claim 1 wherein each transport block isassociated with a transport block size, a modulation and HybridAutomatic Repeat Request (HARQ) parameters.
 4. The network node of claim1 wherein the plurality of transport blocks are associated withdifferent multiple input multiple output (MIMO) streams and precodingweights.
 5. A wireless transmit/receive unit (WTRU) comprising: meansfor transmitting a channel quality indicator (CQI) report to a networknode indicating for each of a plurality of transport blocks a respectiveCQI; and means in response to the transmitted CQI report for receiving aplurality of transport blocks from the network node in a commontransmission time interval using a different Hybrid Automatic RepeatRequest (HARQ) process for each transport block; wherein the HARQprocesses are asynchronous and the network node identifies the HARQprocesses for each transport block.
 6. The WTRU of claim 5 wherein adifferent HARQ process is used for each transport block; wherein theHARQ processes are asynchronous and the network node identifies the HARQprocesses for each transport block.
 7. The WTRU of claim 5 wherein eachtransport block is associated with a transport block size, a modulationand HARQ parameters.
 8. The WTRU of claim 5 wherein the plurality oftransport blocks are associated with different multiple input multipleoutput (MIMO) streams and precoding weights.
 9. A method comprising:transmitting, by a wireless transmit/receive unit (WTRU), a channelquality indicator (CQI) report to a network node indicating for each ofa plurality of transport blocks a respective CQI; and in response to thetransmitted CQI report, receiving, by the WTRU, a plurality of transportblocks from the network node in a common transmission time intervalusing a different Hybrid Automatic Repeat Request (HARQ) process foreach transport block; wherein the HARQ processes are asynchronous and aNode B identifies the HARQ processes for each transport block.
 10. Themethod of claim 9 wherein a different HARQ process is used for eachtransport block; wherein the HARQ processes are asynchronous and thenetwork node identifies the HARQ processes for each transport block. 11.The method of claim 9 wherein each transport block is associated with atransport block size, a modulation and HARQ parameters.
 12. The methodof claim 9 wherein the plurality of transport blocks are associated withdifferent multiple input multiple output (MIMO) streams and precodingweights.
 13. An integrated circuit comprising: means for transmitting achannel quality indicator (CQI) report to a network node indicating foreach of a plurality of transport blocks a respective CQI; and means inresponse to the transmitted CQI report for processing a plurality oftransport blocks from the network node in a common transmission timeinterval using a different Hybrid Automatic Repeat Request (HARQ)process for each transport block; wherein the HARQ processes areasynchronous and the network node identifies the HARQ processes for eachtransport block.
 14. The integrated circuit of claim 13 wherein adifferent HARQ process is used for each transport block; wherein theHARQ processes are asynchronous and the network node identifies the HARQprocesses for each transport block.
 15. The integrated circuit of claim13 wherein each transport block is associated with a transport blocksize, a modulation and HARQ parameters.
 16. The integrated circuit ofclaim 13 wherein the plurality of transport blocks are associated withdifferent multiple input multiple output (MIMO) streams and precodingweights.
 17. A wireless system comprising: a plurality of wirelesstransmit/receive units (WTRUs), each comprising: means for transmittinga channel quality indicator (CQI) report to a network node indicatingfor each of a plurality of transport blocks a respective CQI; and meansin response to the transmitted CQI report for receiving a plurality oftransport blocks from the network node in a common transmission timeinterval using a different Hybrid Automatic Repeat Request (HARQ)process for each transport block; and at least one network nodecomprising: means for receiving the CQI report from one of the WTRUs;and means in response to the received CQI report for transmitting theplurality of transport blocks to the one WTRU in the common transmissiontime interval using the different HARQ process for each transport block;wherein the HARQ processes are asynchronous and the network nodeidentifies the HARQ processes for each transport block.
 18. The systemof claim 17 wherein a different HARQ process is used for each transportblock; wherein the HARQ processes are asynchronous and the network nodeidentifies the HARQ processes for each transport block.
 19. The systemof claim 17 wherein each transport block is associated with a transportblock size, a modulation and HARQ parameters.
 20. The system of claim 17wherein the plurality of transport blocks are associated with differentmultiple input multiple output (MIMO) streams and precoding weights.